A general synthesis of dendralenes

Area of Science:

• Organic Chemistry
• Synthetic Chemistry
• Materials Science

Background:

• Dendralenes are highly branched hydrocarbons with potential applications in materials science.
• Previous synthetic methods for dendralenes were limited in scope and stereoselectivity.

Purpose of the Study:

• To establish a general and stereoselective synthetic approach to substituted dendralenes.
• To demonstrate the utility of these dendralenes in generating complex molecular architectures.

Main Methods:

• Utilized twofold Palladium(0)-catalyzed Negishi couplings of 1,1-dibromoalkenes with alkenylzinc reagents.
• Exploited substrate- and catalyst-controlled selectivity in C(sp2)-C(sp2) bond formation.
• Achieved both (E)/(Z)-stereoselective syntheses of dendralenes.

Main Results:

• Synthesized fifty-one mono- to penta-substituted dendralenes with diverse substituents (alkyl, cycloalkyl, alkenyl, alkynyl, aryl, heteroaryl).
• Reported the first stereoselective syntheses of dendralenes, with twenty-eight examples.
• Demonstrated rapid structural complexity generation using the synthesized dendralenes.

Conclusions:

• The developed synthetic approach provides general access to a wide range of substituted dendralenes.
• The stereoselective synthesis of dendralenes opens new avenues for their application.
• These dendralenes serve as valuable building blocks for complex pericyclic reaction sequences.